title: Further delineation of the clinical spectrum in RNU4ATAC related microcephalic osteodysplastic primordial dwarfism type I.
abstract: We describe five patients from three different families with microcephalic osteodysplastic primordial dwarfism type I (MOPD I), which was molecularly confirmed by homozygosity for the g.51G >A and g.55G >A mutations in RNU4ATAC, respectively. The patients showed the classical phenotype and demonstrated in addition variable degrees of gyration abnormalities and malformations of the callosal body with an interhemispheric cyst. One patient also showed underdevelopment of the cerebellar vermis. This confirms that cortical malformations should be considered cardinal manifestations of MOPD I. Oculocutaneous albinism, brain hemorrhage and chilblains have been found to be associated with MOPD I. The present study showed lack of retinal pigmentation in three patients of whom two had an unusually fair complexion of hair and skin. One patient was found to have a hematoma in the left thalamus. This may indicate that both pigmentary abnormalities and vascular anomalies may be part of the phenotype of MOPD I as well.
authors.affiliation: Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt. ghada.abdelsalam@yahoo.com
authors.forename: Ghada M H
authors.initials: GM
authors.lastname: Abdel-Salam
authors.forename: Mohamed S
authors.initials: MS
authors.lastname: Abdel-Hamid
authors.forename: Nihal A
authors.initials: NA
authors.lastname: Hassan
authors.forename: Mahmoud Y
authors.initials: MY
authors.lastname: Issa
authors.forename: Laila
authors.initials: L
authors.lastname: Effat
authors.forename: Samira
authors.initials: S
authors.lastname: Ismail
authors.forename: Mona S
authors.initials: MS
authors.lastname: Aglan
authors.forename: Maha S
authors.initials: MS
authors.lastname: Zaki
mesh_terms: D000015:Abnormalities, Multiple / Q000235:genetics*; D000328:Adult; D003337:Corpus Callosum / Q000473:pathology*; D004392:Dwarfism / Q000235:genetics* / Q000473:pathology; D005260:Female; D005317:Fetal Growth Retardation / Q000235:genetics* / Q000473:pathology; D006406:Hematoma / Q000235:genetics* / Q000473:pathology; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D008831:Microcephaly / Q000235:genetics* / Q000473:pathology; D009154:Mutation / Q000235:genetics*; D010009:Osteochondrodysplasias / Q000235:genetics* / Q000473:pathology; D010641:Phenotype; D010859:Pigmentation Disorders / Q000235:genetics* / Q000473:pathology; D020718:Ribonucleoproteins, Small Nucleolar / Q000235:genetics*; D013786:Thalamic Diseases / Q000235:genetics* / Q000473:pathology; D055815:Young Adult
chemical_list: D020718:Ribonucleoproteins, Small Nucleolar
keywords: RNU4ATAC; abnormal gyral pattern; interhemispheric cyst; microcephalic osteodysplastic primordial dwarfism I (MOPD I); molar tooth sign; pigmentary disorder; vasculopathy